Sgt. 1st Class Dremiel Byers

A 10-time world champion, Byers is considered one of the most decorated wrestlers in American history. But at the 2008 Olympics, he missed his shot at the medal stand.

That hurt him in more ways than one. Before leaving for China, he had promised his grandfather a gold medal. With sweat pouring off every inch of his considerable frame during the final days of his U.S. training, he vowed to make good on that promise.

Byers' grandpa has passed away since then, "but I still want to keep the promise," he says. "It's always fueling me. It burns me up that I didn't get it while he was here, but people say he's watching, and I believe that."

Even after a grueling string of sparring matches, his face radiates with intensity. In fact, he looks pissed off. "No, I'm just focused," he says.

At this level, even the slightest slip in awareness can mean the difference between winning and losing. At the 2008 Olympics, he says, he didn't win because he wasn't focused enough on scoring early.

"I lost to a guy who didn't score on me. I lost because I didn't score on him. This time I am going to throw the first punch, I promise you that."

In the meantime, his coaches are throwing plenty at him.

"They've been throwing a lot of tough guys at me. There's blood in the water with these sharks — it's a frenzy," he says with a nod to his sparring partners.

"Today, four Olympic gold medalists are on the mat that I'm training on. I want to be one of these guys. There's room for one more."

Sgt. Spenser Mango

Sgt. Spenser Mango quietly says the Serenity Prayer during his warm-ups before every match. He knows he can change some things but not others, so he prays for the wisdom to know the difference.

When he was a kid, Mango's father was gunned down in front of their house in St. Louis. He couldn't change that, but he still found a way to be master of his own destiny: By his junior year in high school, he had won the first of two state wrestling championships.

While attending Northern Michigan University, he took eighth place at the 2008 Olympic Games in Beijing.

After graduating two years ago, he joined the Army so he could continue training as a member of the service's World Class Athlete Program. He says he knew there were things he could improve so that if he got another Olympic shot, he might make the podium.

"I'm coming back a lot more experienced, and I feel like I'm a lot more prepared," says the tightly compact lightweight known as the "littlest guy in the gym with the biggest throw in the show."

Part of his strategy has been getting faster at seizing openings.

"I hesitated a little in Beijing. I got to a couple positions where I could have possibly scored if I had just pulled the trigger faster. If you look at the guys who medaled in '08, those are the guys who just go for it."

Whatever he's doing, it's working. He's been ranked No. 1 in the U.S. every year since Beijing and is a favorite to medal in London.

"I like my chances this time," he says with a sweaty smile after a sparring match.

But he knows that winning a medal will have far less to do with chance than with the wisdom he's gained over the past four years.

Spc. Justin Lester

Spc. Justin Lester used to go by the name Harry. But after joining the Army two years ago, he decided nicknames were for kids.

He's still known as the playful trickster among wrestling teammates, hamming it up on the sly during a recent training-camp visit by a glad-handing general. But on the mat, he's all business.

"I feel great," he says, three weeks before his first bout in London. "My body is beat down, but that's normal for the training we're doing. But as far as hitting my techniques and conditioning, I feel amazing — probably the most positive I've ever felt going into a big tournament."

That says a lot considering the middleweight wrestler has medaled in some of his sport's biggest competitions, only narrowly missing a spot on the 2008 Olympic team.

He knows this is a whole new level of play, but says, "I go to have fun. I know the wrestling will take care of itself if I'm having fun."

So look for him in the opening ceremonies, he says, as much as on the medal stand. "They never show wrestlers in the opening ceremonies," he says with a wry smile. "Who do they show? The gymnasts and the basketball players. So, I've got to sandwich myself in between them."